Switch machine



March 3, 1931.

H. B. TAYLOR SWITCH MACHINE Filed June 8. 1929 Normal Control Wire.

0.55 zoEEo Patented Mar,v 3, 1931 UNITED STATES PATENT OFFICE HERBERT B. TAYLOR, OF ROCHESTER, NEW YORK, 'ASSTGNOR T0 GENERAL RAILWAY SIGNAL COMPANY, OF ROCHESTER, NEW YORK swrrcn MACHINE Application filed June 8,

associated therewith for controlling a switch machine having two field windings.

Among the objects of this invention are to provide contacts and circuit arrangements for remotely controlling the normal and reverse operations of a switch machine over two control wires in conjunction with a common return wire; to provide means whereby the momentum of the motor armature may be dynamically braked at the end of its operations through local circuits; to provide means whereby operation in the opposite direction can not ccur while the armature is being dynamically braked; to provide means whereby the dynamic braking circuit is maintained only while such braking occurs; and to provide an arrangement of circuits so that a cross during operation will cause the motor to stop.

This invention is particularly adaptable to control circuits for switch machines, where the positions assumed by the track switch are repeated in the interlocking tower by means or" constant current source indication circuits as compared with dynamic indication circuits. Also, this invention provides means whereby the last few revolutions of the motor armature generates a current, which is shunted through a snubbing or dynamic braking circuit local to the switch machine. Such an arrangement permits the control of a switchmachine from long distances, whichwould be too great to permit the dynamic brakingot the switch machine to be carried through the contacts of its control le V81, as is the usual practice, due to the high movlng in one direction by the stop pins 5 resistance of the intervening control wires.

ther objects, purposes and charaeteristic features of the invention Wlll be in part obvious from the accompanying drawing and,

in part pointed out as the description of the invention progresses. I

The single figure of drawing shows diagrammatically one specific embodiment of the present invention as applied to a switch" machine havingtwo field windings associated with its armature. i

1929. 'Serial No. 369,395.

Referring now to the single figure of the drawing, the switch machine SM is shown associated with a track switch TS at the east end of a passing siding PS. This track switch TS is controlled to its reverse or norinalposition through a throw bar governed by the motion of the armature A of the switch machine SM in any suitable manner, such for nstance as set forth in the patent to W. K. riowe, No. 1,288,595, dated December 24, 1918. Associated with the throw bar of the switch mach ne SM, is the cam wheelCVV which has a projection CN This cam Wheel CW rotates in a direction denoted by the arrow R when the switch TS moves to'a reverse po- SllllOll, until the projection (TW assumes its dotted position CW In other words, the motion of the camwheel CWV begins with the movement of the trackswitch TS and as sumes its extreme positions at the same time that the track switch TS assumes its extreme posltion. The armature A has associated with it the field windings F and F which are controlled through circuits passing through the contact members 1 and 2 mounted upon the mechanically actuated andelectrically held armaturesB and 4 of the electrio stick relays SR and SR respectively.

The armatures 3 and 4. normally resting on stop pins v3 and 4, respectively, have associated therewith one-way dogs 5 and 6, which are engaged at certain times by the levers 7 and 8. These one-way dogs 5 and G are piv ot ed upon the armatures 3 and 4 respectively and are biased by gravity or other suitable means so that the elongated ends assume a downward position to the extent permitted bythe stop pins 5 and 6. The'manner in which these one-way dogs are prevented from a normal and a reverse control wire in consuch purposes. Tower equipment and other controls associated with the governing of a remotely controlled switch machine may be according to any standard method, such for instance as the control circuits set forth in an application by' W. K. Howe, Ser. No. 337.000, filed February 2, 1929.

It believed that the invention will be better understood from the stand point of operation.

Operation Let us assume that the operator desires to move the track switch TS to a reverse position, which may be accomplished by moving the lever L to its dotted line position. With the lever L in its dotted. line position, positive potential is applied to the field winding,- F and the armature A over a circuit traced follows :-'from the positive terminal of battery ET, through lever L, the reverse control wire. lever 8, wire 9, contact member 1, wires 10 and 11, field winding F armature A, through the common wire to the negative terminal of battery ET. The cam wheelClV now begins to rotate in a direction denoted by the arrow B, as the switch machine begins.

the operation of the track switch TS to a rc verse position. 7

As soon as the projection Cl xl moves suiiicientiy in a counter clockwise direction, the lever 7 moves past the one-way dog 5 without disturbing the armature 3 of a relay SR, and closes the normal control circuit with which it is associated. \Vhen the projection (Wi is moved to its dotted line position Gil at the same time that the track switch TS assumes its reverse position, the lever S ismovcd to its dotted line position, thus moving the armature 4- to its upper position so that a potential which is generated bv the arm aturc A and the field winding F flows through a (ircuit to hold the armature 4 in an energized position until the armature A comes to rest. This snubbing circuit is traced as follows from the positive terminal of the armature A through the field winding F wires 12 and 13, winding of relay SR wire 14:, armature at, through the common wire to the opposite terminal of the armature A.

At the same time that the lever 8 moves to its dotted line position the energizing circuit heretofore traced for the switch machine is broken thecontact associated with lever 8. and is not again completed, until the switch machine has been controlled to operate in a direction indicated by the arrow N for operating the tract: switch TS to its normal position.

As soon as the armature A comes to rest, the induced ci'lrrent, which flows through the snubbing circuit heretofore traced dies out so that the relay becomes dcenergizcd and allows the armature 4 to drop aw; to its deenergized position, allowing the switch machine to be operated for controlling the track switch to its normal position at the option of the operator.

Let us now assume that the switch L is returned to its full line position, at which time positive potential will be applied to operate the switch machine SM through a. circuit traced as follows :-from the positive terminal of battery ET, through the normal control wire, lever 7 in. its dotted line position, wire 15, contact member 2, wires 16 and 12, field winding l armature A, through the common wire to the negative terminal of battery ET. The armature A now rotates in a direction to control the cam wheel ClV in a direction denoted by the arrow N, and to control the track switch TS to a normal position. As soon as the projection CW moves away from engagement with the lever 8, said lever 8 assumes its present full line position, and at the completion of the operation of the track switch TS to a normal position the projectionClW enthe lever 7 and. moves it to its present full line position at the same time forcing the armature 3 to an upper position which it maintains, until the induced snub hing current dies out. This snubbing circuit for the switch machine when operating to the normal position is traced as follows :-from the positive terminal of the armature A through the field winding F wires 11 and 17, winding of relay SP wire .18, armature 3, through the common wire to the opposite terminal of the armature A.

When the armature A comes to rest, the induccd current ceasesto flow through the winding of relay SR and allows the armature 3 to assume its present full line position. Thus.

the operation of the switch machine control, as included within the present invention, has been described to; an oxtcn t including its 'operation from its normal position to its reverse position and its operation from its reverse position back to its normal oosition.

It is noted that a cross between the control wires results in current iiowing through both loo llO

'ield windings, which then neutralize each ther to the extent of stopping the motor. Such a result is highly LlGSlIHbiO QLHCl must be provided for in all arrangements of dynamic braking through local circuits.

Having set forth one specilic illustration of the presentinvention, it desired to be understood that the present invention may be adapted to be usedwith any particular switch machine having two field windings associated with its armature. V

It is to be understood, thatthe cam wheel CW may be controlled in any suitable manner,

one modification of which might be an adaptation to be controlled by a point detector as set forth by C. S. Bushnell in Patent No.

1,517,236, dated -November 25, 1924, inasmuch as a. second projection such as Cl *1 could be placed upon the circumference of cam wheel. CW in such a position that the limited rotation of the cam wheel CWV effected by the point detector would still efi'ect the control of the levers 7 and 8. Also, the cam wheel CWV could be operated to an intermediate position at the beginning of the stroke and to an extreme position at the end of a stroke, in a similar manner tothe above referred to point detector in Patent No. 1,517,- 236, without in any manner. affecting the operation of the present invention.

Although the construction of one embodiment of the invention has been specifically described and the operation and principles thereof explained, nevertheless it is desired to have it understood, that the" form selected is merely illustrative, and does not limit the possible physical embodiments of the idea or means underlying the present invention, as many modifications and adaptations can be made without departing from the spirit of the invention asset forth by the appended claims.

hat I claim is: V

1. Apparatus for operating a distant track switch comprising, a switch machine having a reversible motor, a source of electrical current and means for automatically snubbing the rotation of said motor upon the completion of either normal or reverse operations including, contacts operated by said switch machine for disconnecting said motor from possible connection with said source of curji'ent upon completion of operation of said track switch, contacts operated by said switch machine for shunting said motor upon completion of cithernormal or reverse operations, which contacts are held closed only until said motor ceases rotation, and contacts which complete the control circuit for operation of said switch machine in the opposite direction when said motor ceases to rotate,

whereby the rotation of said armature is "snubbed at the end of each operation through means local to said switch machine.

2. 'Apparatusfor operating a distant tracl; switch comprising, a reversible switch machine having an armature and a field windf ing being controlled from a distant point tion of said armature upon completion of either normal or reverse operations including, contacts mechanically operated by said switch machine for disconnecting said field windings from said manually controlled source of current upon completion of operation of said track switch, contacts mechanically operated by said switch machine for shunting said armature and said field windings, which contacts are held closed only until said armature ceases rotationand contacts which complete the control circuit for operation of said switch machine in the opposite direction when said armature ceases to rotate, whereby the rotation of said armature is snubbed at the end of each operation through means local to said switch machine. I

3. Apparatus for operating a distant track switch comprising, a switch machine having a reversible motor including an armature and field windings which are connected in externally controlled combinations in series with a. manually controlled source of current to produce rotation of said armature in either of two directions over either a normal or a reverse control wirein conjunction with a common wire, and means for automatically snubbing the rotation of said armature at the completion of either normal or reverse operations'of said trackswitch including, contacts mechanically operated by said switch machine for disconnecting a particular control wire from said motor at the completion of operation of said track switch to its correcircuit for the operation of said switch ma chine in the opposite direction when said armature ceasesto rotate, whereby the rotation of said armature is snubbed at the end of each operation through means local to said switch machine.

4. Apparatus for operating distant track switch comprising, a switch machine having a reversible ,motor including two field windings one of which is connected in series with the arn'iature and a source of current to produce rotation in one direction, and the other of which is connected. in series with the ar mature and a source of current to-produce.

rotation in the opposite-direction, means for automatically snubbing therotation of said armature upon the completion either normal or reverse operations including, contacts operated by said switch machine for disconnecting both field windings from possible connection with said source ofcurrent upon completion of operation of said track switch, contacts operated by said switch machine for shunting said armature in series with the particular one of said fields which is deenergized .duringa particular operation, which contacts are held closed only until said armature ceases rotation, and contacts which complete the control circuit for operation of said switch machine in the opposite direction when said armature ceases to rotate whereby the rotation of said armature is snubbed at theend of each operation through means local to said switch machine.

5. Apparatus for operating a distant track switch comprising, a switch machine having a reversible motor including two field windings I matically snubbing the rotation of said armature upon completion of either normal or reverse operation including, contacts operated by said switch machine for disconnecting both field windings from said manually controlled source of current upon completion of operation of said track switch, contacts operated by said switch machine for shunting said armature in series with the particular field which was deenergized during a particular operation, which contactsare held closed only until said armature ceases rotation, and contacts which complete the control circuit for operation of said switch machine in the opposite direction when said armature ceases to rotate,

whereby the rotation of said armature is snubbed at the end of each' operation through means local to said switch machine."

6. Apparatus for operating a distant track switch comprising, a switch machine having a reversible motor including two field windings one of which is connected in series with the armature and a source of current to produce rotation in one direction, and the other of which is connected in series with the armature and a source of current to produce rotation in the opposite direction, means for dynamically braking the rotation of said armature upon the completion of either normal or reverse operations including, a plurality of contacts mechanically controlled by said switch machine, and a plurality of contacts mechanically actuated by said contacts mechanically controlled, which inechanically actuated contacts are electrically held, whereby local circuits, for'dynainically braking said armature of said motor, are com pleted only at the completionof operation of said track switch to either extreme position.

7. Apparatus for operating a distant traclr switch comprising a switch machine having a reversible motor including two field windings one or the other of which is connected in' series with the armature of such motor depending on whether the normal or the reverse wire is connected to a source of current con tacts operated by said switch machine included in said normal and said reverse wire of which the contacts in the norma wire are open in the normal position of said switch machine, are closed in any intermediate posiated by said switch machine for shunti rally tion of said switch machine and open in the reverse position of said switch machine until the rotation of said ari'nature has ceased, and of which the contacts in the reverse wire are open in the reverse position of said switch machine closed in any intermediate position of said switch position and open in the normal position of said switch machine until the rotation of said ai'iiiature has ceased; contacts operated by said switch machine for shunting said armature in series with the particular one of said field windings which is deenergized during a particular operation, a coinmon wire connecting said armature to one side of a source of current, and a control lever for connecting the other side of said source to either the normal or reverse wire, whereby said switch machine motor may be dynamically braked by a circuit wholly local. to said switch machine, and whereby said switch machine may not be controlled for operation in the o; posite direction while said motor is being dynamically braked.

8. Apparatus tor operating a distant track switch comprising, a switch machine having .a reversible motor including two field windings one oi which is connected iii series with the armature and a manually controlled arr .ature in one direction, and the other 01"? which is connected in series with the armature and a manually controlled source of current to produce rotation of said armature in the opposite direction, means for automatically snubbing the rotation of said armature the completion of either normal or reverse operations of said track switch including, contacts mechanically operated said switch machine for disconnecting both field windings from said manually controlled source of current at the completionof opera tion of said track switch to either of its extreme positions, contacts mechanically opersaid armature in series with the particular field winding which is deenergized during a particular operation, which contacts are electriheld closed by the dynamic currents 0t said motor until said armature ceases to rotate, and contacts electrically'held open which released to complete the control circuit for the operation or said switch machine in the opposite direction when said armature ceases to rotate, whereby the rotation of said armature is snubbed at the end or" each operation through means local tosaid switch machine. V

9. in combination with a railway track switch, the combination with a reversible electric motor operated switch machine, a dischine through circuits wholly local to said a switch machine, whereby said switch machine can not be operated in an opposite direction while said switch machine is being dynamically braked.

ll). In combination with a railway track switch, the combination with a reversible elec tric motor operated switch machine,' a distant control means for controlling said switch machine to operate said track switch to either of two extreme positions, and contact means mechanically operated at the end of each operating stroke of said switch machine for closing a dynamic braking circuit including means for maintaining said braking circuit closed by the dynamic indication current flowing therein.

In testimony whereof I affix my signature.

HERBERT B. TAYLOR. 

